<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link rel="stylesheet" href="../css/bootstrap.css">
    <title>Bootstrap图片</title>
</head>
<body style="background-color: gray;">
    <!-- 图片的样式化 -->
    <img src="../images/img.png" class="rounded" alt="">
    <img src="../images/img.png" class="rounded-circle" alt="">
    <!-- 可缩放的图片 -->
    <img src="../images/img.png" class="img-thumbnail" alt="">
    <!-- 响应式图片 -->
    <img src="../images/img.png" class="img-fluid" alt="">
    <hr>
    <img src="../images/img.png" alt="" class="float-left" width="200" height="200">
    <img src="../images/img.png" alt="" class="float-right" width="200" height="200">

    <!-- 在网页中嵌入一个指定长宽比例的iframe -->
    <div class="embed-responsive embed-responsive-21by9">
        <iframe  class="embed-responsive-item" src="https://www.bilibili.com/"  frameborder="0"></iframe>
    </div>

    
</body>
</html>